On-the-main



Patented Aug. 3, 1926.

UNITED STATES PATENT OFFICE.

ARTHUR ZITSCHER AND ROBERT SCHMITT, OF OFFENBACH-Ofi-THE-MAIN, GERMANY,

ASSIGNORS T L. G. FARBEJFINDUSTRIE AKTIENGESELLSCHAFT, OF FRANKFORT- ON-THE-MAIN, GERMANY.

DI-ACYLACETYL-DIAMINO COMPOUNDS OF THE DIARYL SERIES AND PROCESS OF MAKING SAME.

No Drawing. Application filed May 15, 1923, Serial No. 639,213, and in Germany August 28, 1922.

Our invention relates to a process of makingdi-acylacetyLdmmmo compounds of the general formula:

Y.CO.CH .CO.NH.X.NH.CO.CH,,.CO.Y,

wherein X means a diarylresidue, Y any radicle of the hydrocarbon series containing at least one and not more than six carbon atoms, aliphatic as well aromatic radicles being included under this term. said process consisting in reacting upon diamino bases of the diary] series acvlacetic acid esters, such as acetoacetic acid ester or its homologues or analogues, in the presence of a solvent or diluent.

In the Monatshe-ftc fiir Chemie, Vol. 19, page 693, llcidrich has described (ii-acetoa cei'ylbcnzi din. obtained by heating benzidin with acctoaeetic acid ester at 110 to not over 120. (All temperatures in this specification are given in centisrrade degrees.) But according to Heidrichs method a large amount of by-products is always formed. and therefore a. complicated rectification is necessary for obtaining the di-acetoacetylbenzidin in a serviceable form. The yield is therefore only about 10 to 15 p. c. of the theoretical yield. Besid s by increasing the temperature a little over 120 the produce becomes easily 9 resinous, as Heidrich describes, so that therefrom not a particle of a serviceable product is obtained (page 693, lines 20-22). By using the various solvents or diluents such as e. g. hydrocarbons of the benzene se- 35 ries, chlorobenzene. nitrobenzene, naphthalenc or a great surplus of the acylacetic acid ester used for our process generally the diacylacetyl-diamino compounds of the diaryl series are obtained in a good yield and of an CHglCCLCHnCO-NH 80 Example 2.

61 parts of benzidin are'dissolved in 850 parts of solventn-aphtha, and to the boiling solution 130 parts of acetoacetic a'cid ester are 35 added slowly while stirring. The mixture Ewample 1.

Into a boiling mixture of 150 parts of acetoacetic acid ester and 800 parts of chlorobenzcne 71 parts of ortho-tolidin are poured while stirring. The mixture is kept boiling, until the splitting oif of alcohol is finished. After cooling down the separated pulp of crystals is filtered and dried. If necessary some amin, which has not reacted. is removed by means of dilute hydrochloric acid and 101 parts, that is 80 p. c. of the theoretical yield, of di-aceto acetyl-orthotolidin are obtained as a crystal powder, almost colorless and melting at 200. Crystallized from alcohol it is obtained in finelustrous needles, melting at 204-205? (not corrected) under decomposition. It is soluble in alcohol, glacial acetic \acid and nitrobenzone, less soluble in acetone and acetic acid ester, insoluble in benzene, ether and carbon tetrachloride, having probably the formula:

82 parts, that is 70 p. c. of the from glacial acetic acid, at 234-235 corrected) under decomposition.

When using toluene instead of solvent naphtha, the yield is a little smaller.

Ewample 3.

(not

scribed in Example 1. By this treatment 96 parts of di-acetoacetyl-ortho-dianisidin, decomposing at 164, that is 70 p. c. of the theoretical yield, are obtained. It forms from alcohol fine feebly yellowish needles, melting at Mil-165 (not corrected) under decomposition. It is solublein alcohol, glacial acetic acid and nitrobenzene, less solable in benzene insoluble in ether and car- Example 4.

. 71 parts of ortho-tolidin are dissolved in 850 parts of solvent naphtha and to the boiling solution 130 parts of benzoylacetic acid ester are added. The mixture is kept boiling, until the reaction is finished, and dibenzoylacetyl-ortho-tolidin is isolated, as above described. The yield is 70 p. c.'of the theoretical yield. Di-benzoylacetylortho-tolidin acetic acid in fine, colorless and lustrous needles, melting at 233 (not corrected) under decomposition. It is little soluble in alcohol and toluene, more soluble in glacial acetic acid and pyridine.

All these di-acylacetyl-diarylides are soluble in a dilute caustic soda solution.

With other bases and other di-acylacctic acid esters the reattion can be conducted in a similar manner.

The following table gives the properties of some of the compounds obtainable acis crystallized from dilutebon tetnachlori e. cording to the present process:

Melting point Di acylscetyl compound. Aspect. 'gjjfg l ng t orsolubility.

Di-ecstoacetyl-orthc-toli- Fine lustrous colorless Alcohol... Zoe-206 under Boluble in alcohol. glacial acetic acid and nitrodim n dles, decomposibenzene, less soluble in acetone and acetic acid tion. :sger, 1ipsolluble in benzene, ether and carbon e me or c. Dl-eeetoacstyl=orthocr- Colorless flakes oi crystals. Dilute alcohol. Decomposing Soluble in glacial acetic acid, acetic acid ester and thd-dichlorobenzidin. at'145-147". acetone, ess soluble in ether and benzene. Di-acetoecetyl-meta-meta- Colorless needles, united Dilum alcohol. Decomposing Soluble in glacial acetic acid, acetic acid ester and dl-chlorobenzidin. to clusters. at 212. acetone, css soluble in ether and benzene. Di-acetoscetyl-dienieidin.. Fins, iesbly yellowish Alcohol 164-165" under Soluble in alcohol glacial acetic acid and nitron edles. decomposibenzene, less soluble in benzene, insoluble in tion. ether and carbon tetrachloride. Di-benzoylacetyl-benzidln Fine yellowish crystalline Dilute pyridin 248 under de- Soluble in glacial acetic acid and pyridine, insollpowder. composition. uble in ether. Di-benzoylscetyl-ortho-to- F ne, colorless lustrous Dilute acetic 233 under de- Soluble in glacial acetic acid and pyridine, less lidin. needles. acid. composition. soluble in alcohol and toluene. 4

1 In testimony names, this 28th day of April 1923.

3 All new articles the di-acylacetyldiamln compounds of the general formula:

Y.CO.CH .OO.NH.X.NH.CO.CH .001,

wherein X means a substituted diaryl residue, Y any radicle of the hydrocarbon series containing at least one and not more than six carbon atoms.

4. As a new article di-acetoacetyl-orthctolidin of the formula:

that we claim the foregoing as our invention, we have signed our ARTHUR ZITS CHER. 

